OptionalwebgpuModule?: Promise<__module>The three/webgpu chunk, prefetched as soon as the adapter answered
(not after requestDevice, since getting an adapter already means
this session is going WebGPU). Threaded through so the eventual
WebGPURenderer construction reuses this fetch instead of starting
a second one.
The result of Luxar's core-adapter negotiation, before constructing Three's renderer.